3.3.5 Reginal Differences

Figure 3.4: Primary energy use in the buildings sector, 1971-1995.

There are significant regional differences in levels of energy use and related
GHG emissions from the buildings sector. Table 3.4 presents
1995 buildings sectors fuels, electricity, primary energy, and CO2
emissions and historical growth rates for the 1971 to 1990 and 1990 to 1995
periods for four regions (Price et al., 1998, 1999). Figure
3.4 provides a graphical presentation of the data on primary energy use
in buildings, with the fourth region (Rest of World) desegregated into Middle
East, Latin America, and Africa. Three very important trends are apparent:

Developed countries have by far the largest CO2 emissions from
the buildings sector and have exhibited a relatively steady long-term trend
of annual primary energy growth in the 1.8% to 1.9% range (with lower growth
through 1985 and higher growth thereafter).

Since the late 1980s, energy use and related CO2 emissions from
buildings in the developing countries, particularly in the AsiaPacific
region, have grown about five times as fast as the global average (and more
than twice as fast as in developed countries).

The growth rate of buildings energy use globally has declined since
1990 because of the economic crisis in the EITs. The world other than the
EITs continued its long-term trend (1971-1995) of annual energy growth in
the 2.8% to 2.9% range.

The average annual increase in urban population was nearly 4.0% per year in Asia
and Rest of World regions. This increased urbanization led to increased use of
commercial fuels, such as kerosene and liquefied petroleum gas (LPG), for cooking
instead of traditional biomass fuels. In general, higher levels of urbanization
are associated with higher incomes and increased household energy use, including
significantly increased purchase and use of a variety of household appliances
(Sathaye et al., 1989; Nadel et al., 1997, Sathaye and Ketoff, 1991). Wealthier
populaces in developing countries exhibit consumption patterns similar to those
in developed countries, where purchases of appliances and other energy-using equipment
increase with gains in disposable income (WEC, 1995a).

Note:
Data sources are IEA, 1997a; IEA, 1997b, IEA, 1997c and BP, 1997. For the
EIT region only, energy data from British Petroleum were used instead of
IEA data. Thus, primary energy and CO2 emissions for the EIT
region cannot be compared. For a more detailed description of the data,
see Price et al., 1998, 1999.

Between 1971 and 1990, global primary energy use per capita in the buildings
sector grew from 16.5GJ/capita to 20GJ/capita. Per capita energy use in buildings
varied widely by region, with the developed and EIT regions dominating globally.
Energy use per capita is higher in the residential sector than in the commercial
sector in all regions, although average annual growth in commercial energy use
per capita was higher during the period, averaging 1.7% per year globally compared
to 0.6% per year for the residential sector.

Energy consumption in residential buildings is strongly correlated with household
income levels. Between 1973 and 1993, increases in total private consumption
translated into larger homes, more appliances, and an increased use of energy
services (water heating, space heating) in most developed countries (IEA, 1997d).
In developed countries, household floor area increased but household size dropped
from an average of 3.5 persons per household in 1970 to 2.8 persons per household
in 1990. These trends led to a decline in energy use per household but increased
residential energy use per capita (IEA, 1997d).

In the commercial sector, the ratio of primary energy use to total GDP as well
as commercial sector GDP fell in a number of developed countries between 1970
and the early 1990s. This decrease, primarily a result of increases in energy
efficiency, occurred despite large growth in energy-using equipment in commercial
buildings, almost certainly the result of improved equipment efficiencies. Growth
in electricity use in the commercial sector shows a relatively strong correlation
with the commercial sector GDP (IEA, 1997d).

Space heating is the largest end-use in the developed countries as a whole
and in the EIT region (Nadel et al., 1997), although not as important in some
developed countries with a warm climate. The penetration of central heating
doubled from about 40% of dwellings to almost 80% of dwellings in many developed
countries between 1970 and 1992 (IEA, 1997d). District heating systems are common
in some areas of Europe and in the EIT region. Space heating is not common in
most developing countries, with the exception of the northern half of China,
Korea, Argentina, and a few other South American countries (Sathaye et al.,
1989). Residential space heating energy intensities declined in most developed
countries (except Japan) between 1970 and 1992 because of reduced heat losses
in buildings, lowered indoor temperatures, more careful heating practices, and
improvements in energy efficiency of heating equipment (IEA, 1997d; Schipper
et al., 1996).

Water heating, refrigeration, space cooling, and lighting are the next largest
residential energy uses, respectively, in most developed countries (IEA, 1997d).
In developing countries, cooking and water heating dominate, followed by lighting,
small appliances, and refrigerators (Sathaye and Ketoff, 1991). Appliance penetration
rates increased in all regions between 1970 and 1990. The energy intensity of
new appliances declined over the past two decades; for example, new refrigerators
in the US were 65% less energy-intensive in 1993 than in 1972, accounting for
differences in size or performance (IEA, 1997d; Schipper et al., 1996). Electricity
use and intensity (MJ/m2) increased rapidly in the commercial buildings
sector as the use of lighting, air conditioning, computers, and other office
equipment has grown. Fuel intensity (PJ/m2) declined rapidly in developed
countries as the share of energy used for space heating in commercial buildings
dropped as a result of thermal improvements in buildings (Krackeler et al.,
1998). Fuel use declined faster than electricity consumption increased, with
the result that primary energy use per square meter of commercial sector floor
area gradually declined in most developed countries.

The carbon intensity of the residential sector declined in most developed countries
between 1970 and the early 1990s (IEA, 1997d). In the service sector, carbon
dioxide emissions per square meter of commercial floor area also dropped in
most developed countries during this period in spite of increasing carbon intensity
of electricity production in many countries (Krackeler et al., 1998). In developing
countries, carbon intensity of both the residential and commercial sector is
expected to continue to increase, both as a result of increased demand for energy
services and the continuing replacement of biomass fuels with commercial fuels
(IEA, 1995).